Affiliation:
1. Dalian University
2. Dalian University of Technology
Abstract
HfO2films were sputter deposited under varying substrate temperatures (Ts) and their structural and morphological characteristics, optical properties were systematically studied by means of X-ray diffraction (XRD), atomic force microscope (AFM), and UV/VIS spectrophotometry. A statistical analysis based on multifractal formalism shows the uniformity of the height distribution increases asTsis increased and the widths Δαof multifractal spetra are related to the average grain sizeD(-111)as Δα∼ [D(-111)]-0.83. The monoclinic HfO2is highly oriented along (-111) direction with increasingTs. The Lattice expansion increases with diminishing HfO2crystalline size below 7 nm while maximum lattice expansion occurs with highly oriented monoclinic HfO2of crystalline size about 14.8 nm. The film growth process atTs≥ 200°C with surface diffusion energy of ∼ 0.29 eV is evident from the structural analysis of HfO2films.
Publisher
Trans Tech Publications, Ltd.